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Thread: Displaylist behavior

  1. #1
    Intern Contributor
    Join Date
    Feb 2000
    Location
    Bremen, Bremen, Germany
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    58

    Displaylist behavior

    Hi,

    I'm doing a large outdoor engine. At first I have rendered my terrain into a single display list.
    Since testing the visibility for all triangles of my landscape is to slow, I decided to divide
    my landscape into sectors. Each sector is rendered into s displaylist. I have implemented this and
    wanted to do the visibility detection. But it seems like this is unnecessary! OpenGL already seems not
    to bother with display lists that lie outside the view. My engines runs with 3x the FPS cause the
    terrain is clipped by opengl. I'm using the nVidia ICD on a GeForceDDR. Is this behavior to to a fast
    cliiping on display lists implementation depend ? Should I rely on it ? Should I code my own alogrithm
    to filter out invisible display lists or should I let OpenGL do the work ?

    Tim

  2. #2
    Advanced Member Frequent Contributor
    Join Date
    Feb 2000
    Posts
    569

    Re: Displaylist behavior

    You just felt the GeForce Power!!!!

    If the display list is too big, some optizimisations by the drivers cannot be done. If you chew it smaller ones it will be much faster.

    Don't count on openglClipping, because still all the vertices of your terrain are calculated(it just that GeForce DDR! lucky you is fast).

    If you do your own visibility, you'll gain more precious fps that can be use for other SFX.

  3. #3
    Intern Contributor
    Join Date
    Feb 2000
    Location
    Bremen, Bremen, Germany
    Posts
    58

    Re: Displaylist behavior

    yes, GeForce rulez ;-))
    It just seems that nVidia GL uses some very fast clipping for sorting out complete displaylists. It seems that it calculates a bounding box and test then for visibility. But I'm afraid other implementations dont't do ;-)

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